A question we are often asked is
WHICH IS THE BEST TYPE OF ROTATOR?
Even small rotators will turn a large antenna, but it takes a well-designed one to
a) Resist windmilling (i.e. rotator turning on it's own)
b) Resist breaking up under severe storm conditions.
c) Last you for many years of service
We've seen lots of rotators, including broken ones. It's clear that some are better designed than others, particularly as far as windmilling and damage is concerned.
To summarise what we have found, there are three classes of rotators.......
The Best
- driven by a non-reversible worm-wheel gear directly on the final gear, with lubrication by oil-bath (Prosistel)
The Next Best
- driven by a worm-drive motor through a gear train, grease lubrication on gears (Create and M2)
Pretty Good
- positive electrically-operated brake-wedge arrangements (HyGain Ham-series and T2X Tail-twister)
Keep Your Fingers Crossed
- anything which relies on planetary gears and the inertia of the motor to prevent turning (Yaesu, Kenpro, HyGain AR22 and CD44, and TV antenna rotators).
This isn't to say that there aren't plenty of people out there happily using planetary gear rotators. There are, but we see lots of broken planetary gear motors, and hardly any of the other types. If you are considering a new or replacement rotator, the above pointers may save you much agony later!
Azimuth Rotators - Comparison Table